Over time, the portion sizes of restaurant meals have been increasing. Can offering a to-go box prevent overeating? In a recent experiment involving 53 women, 27 were randomly assigned to be informed before the meal that their remaining food would be packaged up in a to-go box. The remaining 26 women weren't told anything about a to-go box. Furthermore, each of the 53 women was randomly assigned a different portion size: regular, 25% more than regular, 50% more than regular, and 75% more than regular. At the end of each meal, the total number of calories consumed was recorded. Women who were given information about the to-go box tended to eat less, especially at the higher portion sizes. Why was it necessary to perform an experiment rather than simply asking women if they typically get to-go containers? It was necessary to perform an experiment rather than simply asking women if they typically get to-go containers to enable the researchers to make a general claim about all women. It is necessary to perform an experiment rather than simply asking women if they typically get to-go containers but the sample size is too small so the researchers are not able to draw any conclusions. It was necessary to perform an experiment rather than simply asking women if they typically get to-go containers to eliminate confounding and to enable the researchers to draw cause-and-effect conclusions. It was necessary to perform an experiment rather than simply asking women if they typically get to-go containers to eliminate confounding and to enable the researchers to draw cause-and-effect conclusions about women from different age groups. Question 2 An experiment is performed on plants to see how different liquids affect plant growth. Each plant in the experiment is given a different liquid; water, apple juice, or milk. Each plant has the same amount of soil. In this investigation, sunlight would be a(n) ... O Confounding Variable O Response Variable O Treatment O Explanatory Variable Question 3 2.5 pts 2.5 pts Many people like to surf, but there are dangers involved, including the possibility of a shark attack. In response to this concern, many companies have produced shark repellents that surfers can try (e.g., magnetic bracelets, scented wax). But do they work? Researchers tested 5 different products in a clever experiment. They built 5 surfboards, each having one of the deterrents. A 6th board had no deterrent, but was otherwise identical to the other boards. Then they attached some raw tuna about 30 centimeters below each board, where a surfer's foot might be, and recorded the behavior of sharks that came near the board. The shark ate the bait in 96% of the trials with the 6th board, but only 40% of the time with the most effective deterrent. Why was it necessary to include the 6th board with no deterrent? By using a 6th board with no deterrent, the researchers would be able to prove cause-and-effect and prove that when using the most effective shark deterrent reduces the percentage of shark attacks. By using a 6th board with no deterrent, the researchers would be able to make a general claim about all species of sharks in the ocean. O This board, with no deterrent, would serve as a baseline to determine how much less frequently the shark ate the bait for each of the deterrents. It is necessary to include a board with no deterrent to save the researchers time and money when conducting this experiment. Question 4 2.5 pts Over time, the portion sizes of restaurant meals have been increasing. Can offering a to-go box prevent overeating? In a recent experiment involving 53 women, 27 were randomly assigned to be informed before the meal that their remaining food would be packaged up in a to-go box. The remaining 26 women weren't told anything about a to-go box. Furthermore, each of the 53 women was randomly assigned a different portion size: regular, 25% more than regular, 50% more than regular, and 75% more than regular. At the end of each meal, the total number of calories consumed was recorded. Women who were given information about the to-go box tended to eat less, especially at the higher portion sizes. If the researchers used every possible combination to form the treatments, how many treatments were included in the experiment?